The instant invention relates to reinforced sealing materials. More particularly the present invention relates to a reinforced laminate sealing strip and a method of manufacturing such a sealing strip type that is commonly utilized in sealing the edges of various parts of an automobile in mated fashion to one another.
For example, glass windows need to be sealed when in communication with the door frame. Most automotive doors have a body envelope that is created by two door panels, an inner and an outer which are generally in parallel spaced-apart relation to one another. An extendable pane of window glass is nested in the parallel opening between the door panels. In addition, a window regulator is provided for selectively moving the glass pane in and out of the door envelope to open and close the window opening of the door. In many vehicles, the vehicle door includes a door window frame extending from the top of the door panels and extending over the top of the window opening for enclosing the window. This door window frame has a seal, typically called weather stripping, which is installed into the door window frame to seal the perimeter edges of the window glass when the window glass is in its uppermost position.
Additionally, a weather stripping seal of similar construction is employed in other locations around the vehicle where a weather tight seal is required between an operable component of the vehicle and the vehicle body such as the trunk lid and the doors. In these locations, generally a metal fin is formed as part of the vehicle body panels around the perimeter of these openings. The sealing material is compressed between the body panels and the operable component to form a weather tight seal when the component is in a closed position.
A typical weather sealing strip has a U-shaped retention portion that contains a reinforcing carrier and is installed over an edge of the sheet metal of the door window frame or other body opening that surrounds the perimeter of the opening. Connected with the retention portion is a portion of the weather stripping referred to as the sealing member or the glass seal. The sealing member is typically shaped as an inverted U-shaped section with respect to the retention portion or a compressible bulbous section and is laterally joined thereto. The glass seal typically has flocked wings, which seal against the side of the glass when the glass is in the closed position and inserted within the U shape of the glass seal. The bulbous type profile is typically compressed against the operable component when the component is in a closed position.
The carrier is typically reinforced by a roll formed or stamped thin metal member. Typical materials utilized for the carrier reinforcement are cold rolled steel, stainless steel or aluminum. After the carrier is formed, it is passed through an extruder and covered with a polymeric material, typically an elastomeric material such as rubber. The interior of the retention portion may or may not have formed barbs to assist the weather stripping in retaining itself to the sheet metal of the door once it is pushed over the edge of the sheet metal.
In most vehicles however, the openings around the windows and doors do not have edges that are square or parallel to opposing edged thereto and the corners are typically radiused. For example, the lateral edge of a front door window frame at the front end is inclined due to the inclination of the automobile's “A” pillar. The door window frame, generally rearward of the “A” pillar, curves into a second horizontal linear section called the header which usually runs longitudinal with the vehicle. A third linear section of the door window frame is oriented generally vertically and is usually conformed to the shape of the “B” pillar. Between the “A” pillar and the top of the door window frame, is a first curved section. Between the top of the door window frame and the “B” pillar portion of the window opening is a second curved section. Most carrier materials, which are formed using thin metal reinforcement, are not flexible enough to bend to conform to the small radiuses of the curves of the door window frame. Therefore, in these applications, a first length of weather stripping is utilized to seal the first linear section of the window. A second length of weather stripping is used to seal the second linear section of the window, and a third length of weather stripping was utilized to seal the third linear section.
Many known door windows require an additional molded joint component to be installed between two linear sections to seal the curved sections. The molded joint however has a dissimilar cross-section than that of the adjoining linear sections. Another method used to seal the radius sections is to notch the carrier to allow it to fold and then mold a polymeric patch into the notched area. The prior sealing systems either do not provide a constant sectioned extrusion through the corners and therefore lack firm retention to a seal-mounting flange of the door window frame at these locations, or are limited to relatively large radiuses, which would otherwise cause seal wrinkling or buckling. Lack of retention to the seal to the mounting flange or wrinkling or buckling of the seal degrades the integrity of the seal. Also, without additional operations, many molded corners lack the low friction areas between the window glass and seal. The lack of low friction causes squeaks and mandates that higher window regulator forces be utilized to ensure closure of the window.
While in most instances, the metal used as the carrier within the extruded seal, such as stamped metal reinforcing, is not flexible enough to corner through the small radius required. Most carrier material, that is flexible enough to corner through the small radius, does not have the tensile strength required to process the carrier material through the roll forming mill or the polymer injection molding and/or extruding processes. Prior art attempts to overcome these difficulties include the replacement of the stamped or rolled metal reinforcing carrier with an undulating knitted wire material. Since the undulating wire has little tensile strength, the knitted or woven fabric material is added between each pass of the wire to provide longitudinal stability and maintain the spacing of the wires as the carrier is subjected to the extrusion process. In these instances, the equipment required to weave the fabric carriers with the wire strand is expensive and requires a high degree of calibration and maintenance thus increasing the cost and manufacturing time required to produce the reinforcing material. In addition, the reinforcing carriers are generally produced by one manufacturer and supplied to another manufacturer as raw material for further extrusion and incorporation into a finished weather stripping product.
Finally, in all of the prior art weather stripping materials, the reinforcing carrier material is directly crosshead extruded into the finished product. While this process proves to be expedient from a manufacturing standpoint, the finished product tends to have ribbed pattern that appears in the surface of the finished extrusion corresponding to the locations of the reinforcing members. This appearance is referred to as the “hungry horse” and is aesthetically unattractive and, therefore, not considered desirable in the weather stripping industry.
It is therefore desirable to provide a process that provides a reinforcing web that can be employed as raw material for further extruding weather stripping. It is a further object of the present invention to provide a reinforcing carrier that maintains longitudinal stability during the fabrication process while allowing the required flexibility required in the finished product. It is another object of the present invention to provide a reinforcing carrier that can be incorporated into a weather stripping extrusion that minimizes or eliminates the “hungry horse” appearance.